AuthorsM. Jørgensen, and E. Escott
TitleRelative and absolute estimates of software development effort
AfilliationSoftware Engineering
Project(s)Department of IT Management
Publication TypeJournal Article
Year of Publication2020
Journalsubmitted to a journal

Context: There are many claims, but not much evidence, about advantages connected with the use of relative instead of absolute estimates.

Objective: We test the claims that people are better at giving relative estimates, that producing relative estimates is faster, and that, relative effort to a large extent is developer-independent.

Method: We conducted two experiments. The first experiment addresses the two first claims and analyses the estimates from 102 professional software developers randomly allocated to providing relative or absolute estimates of software development effort and other quantities. The second experiment addresses the third claim and analyses the actual efforts from 20 professional software developers completing the same five programming tasks.

Results: We found, for most of the estimation tasks, only smaller differences between relative and absolute estimates, which is consistent with a similarity in underlying estimation processes. The time spent completing the estimation work was higher or the same for those using relative estimation. We found a strong developer-dependency in relative use of effort, suggesting that relative estimates are far from developer-independent.

Conclusions: The results give no support to the claims that relative estimation is better, faster or that relative effort to a large extent is developer-independent.

Citation Key27618